UNH/CCOM-JHC : Center for Coastal and Ocean Mapping/Joint Hydrographic Center, University of New Hampshire
2007-08-01
Gulf of Mexico Florida Escarpment ASCII XYZ Acoustic Backscatter data.
Gridded (100 m/pixel) full coverage, processed Acoustic Backscatter Data - Data were first reduced for position, elevation, orientation, water-column sound-speed and refraction effects and are provided as a cleaned gridded Acoustic Backscatter ASCII XYZ dataset. All soundings and ancillary raw and reduced data were provided with quality flags, indicating whether these data were rejected or deemed to be outside deliverable survey specifications.
The National Oceanic and Atmospheric Administration (NOAA), on behalf of the United States Government, has a requirement to carry out surveys of specific regions on the continental margin (slope and rise) in the northern Atlantic Ocean in order to obtain multibeam bathymetry and co-registered calibrated acoustic backscatter. These data are required to support a potential claim for extended jurisdiction by the United States under United Nations Convention on the Law of the Sea (UNCLOS) Article 76. The requirement is for the collection and processing of high quality, full-coverage multibeam sonar data in water depths of approximately 2000 to 5000 m in order to precisely define the location of the 2500-m isobath and the "foot of the slope" as defined under UNCLOS Article 76. As part of their NOAA-funded research program, University of New Hampshire (UNH) researchers oversaw data acquisition, processing and archiving of the data collected during the cruise.
md5_checksum value: 22af6afdca0a6a223392ee829fef0f26 **GulfOfMexico_FloridaEscarpment_ASCII_mos.zip . digestIT 2004 was used to generate the md5_checksum value, please see http://www.openoffice.org/dev_docs/using_md5sums.html#lin for more information on how to validate the md5_checksum value. The cruise report for this cruise is located at: http://ccom.unh.edu/publications/Gardner_07_cruise_report_NR07-1.pdf. UNH was responsible for generating gridded bathymetry data sets at sea. An additional set of gridded data was produced by UNH. The UNH grid was generated from the UNH-processed sounding data. The shaded-relief models are illuminated from an azimuth of 315 degrees with a sun elevation of 45 degrees. Information about UNH Center for Coastal and Ocean Mapping field activity are online at http://ccom.unh.edu/unclos/reports.htm.
2007-06-21
2007-07-08
Publication Date
None planned
-85.839500
-84.440000
27.359000
24.879500
None
Acoustic Backscatter
Extended Continental Shelf Project Glossary of Terms
Foot of the slope
Uncontrolled - Departure
Mobile, AL
Uncontrolled - Arrival
Mobile, AL
NASA/GCMD Location Keywords
Ocean > Atlantic Ocean > North Atlantic Ocean > Gulf Of Mexico
NR0701
RV Northern Resolution
Kongsberg Simrad EM120 12-kHz Multibeam Echosounder and a GeoAcoustics GeoPulse 5430A 3.5-kHz sub-bottom profiler
None
The content on this website, including but not limited to the Grid Generations, are the Copyright of the University of New Hampshire - © 2005 The University of New Hampshire and its Center for Coastal and Ocean Mapping/Joint Hydrographic Center, Durham, NH 03824.
Any redistribution or reproduction of part or all of the contents in any form is granted with the following restrictions:
• You must attribute ownership of the copyrighted contents of this website to the rightful owner, the University of New Hampshire.
The UNH Center for Coastal and Ocean Mapping operates in partnership with the National Oceanic and Atmospheric Administration.
UNH/CCOM-JHC : Center for Coastal and Ocean Mapping/Joint Hydrographic Center, University of New Hampshire
James V. Gardner
Research Professor
Mailing and Physical Address
Chase Ocean Engineering Lab, 24 Colovos Road
Durham
NH
03824
USA
(603) 862-3473
(603) 862-0834
jim.gardner@unh.edu
9:00 AM - 5:00 PM Eastern
James V. Gardner - UNH/CCOM-JHC : Center for Coastal and Ocean Mapping/Joint Hydrographic Center, University of New Hampshire
None
Unclassified
None
A Kongsberg Simrad EM120 12-kHz Multibeam Echosounder and a GeoAcoustics GeoPulse 5430A 3.5-kHz sub-bottom profiler sonar was used with effective beam widths no greater than 1deg x 2deg (transmit fore-aft x athwart ships) at -3 dB, with swaths of ~7.4 times water depth in water depths between 1000 m and 3400 m, with depth accuracies of the swath of better than +-0.3% of water depth at these depths. All data meets this specification. Descriptions of the systems and offsets applied can be found within the cruise report at http://ccom.unh.edu/publications/Gardner_07_cruise_report_NR07-1.pdf. In addition to bathymetry data, full time-series backscatter values were recorded across each beam footprint. Backscatter values were corrected for outgoing signal strength, receiver gains, spherical spreading, and attenuation.
Unknown
Complete
Horizontal positioning of the vessel was determined using C&C Technologies C-Nav Real Time Gypsy (RTG)-aided DGPS integrated into a TSS DMS-05 motion sensor. Positioning is accurate to better than 0.1 meters (at 95% confidence) during all surveying. All positioning is referenced to the WGS84 Datum.
Depth errors (at the 95% confidence level) are smaller than +-1% of the observed water depth as determined by cross lines.
The bathymetry and backscatter data were collected and processed by C&C Technologies, Inc., Lafayette, LA along a continuous swath perpendicular to the direction of the ship using a Kongsberg Simrad EM120 12-kHz Multibeam Echosounder and a GeoAcoustics GeoPulse 5430A 3.5-kHz sub-bottom profiler sonar system. CC0M-UNH generated gridded bathymetry and acoustic backscatter data sets at sea. Individual ping and beam data were edited for fliers and then merged with navigation. A bathymetric grid and a backscatter mosaic were generated. Data were gridded at a grid size 100 m/pixel. These data were output in longitude, latitude, depth format as ASCII XYZ files and compressed with WinZip.
2007-07-08
UNH/CCOM-JHC : Center for Coastal and Ocean Mapping/Joint Hydrographic Center, University of New Hampshire
James V. Gardner
Research Professor
Mailing and Physical Address
Chase Ocean Engineering Lab, 24 Colovos Road
Durham
NH
03824
USA
(603) 862-3473
(603) 862-0834
jim.gardner@unh.edu
9:00 AM - 5:00 PM Eastern
Raster
Grid Cell
2480
1400
0.0
0.0
Decimal Degrees
WGS84
WGS84
6378137.00
298.257224
Backscatter Coordinate System
0.0
8-bit digital number (DN); DB = -(255-DN)/2
Explicit elevation coordinate included with horizontal coordinates
Instantaneous sea level
Better than 1% of water depth
percentage of water depth
Explicit depth coordinate included with horizontal coordinates
UNH/CCOM-JHC : Center for Coastal and Ocean Mapping/Joint Hydrographic Center, University of New Hampshire
James V. Gardner
Research Professor
Mailing and Physical Address
Chase Ocean Engineering Lab, 24 Colovos Road
Durham
NH
03824
USA
(603) 862-3473
(603) 862-0834
jim.gardner@unh.edu
9:00 AM - 5:00 PM Eastern
GulfofMexico_FloridaEscarpment_ASCII_mos
The University of New Hampshire through the Center for Coastal and Ocean Mapping/Joint Hydrographic Center (“UNH/CCOM-JHC”) makes this data and information available on its web site to enhance public knowledge and promote education. UNH/CCOM-JHC, however, cannot guarantee accuracy and reliability of this data. UNH/CCOM-JHC also retains the right to change any content on its website without prior notice. Neither UNH nor any agency thereof, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any material, nor represent that its use would not infringe on privately owned rights.
Information provided on this web site should not be used for navigational purposes. The materials on this web site are provided with the understanding that they are not guaranteed to be usable, timely, accurate, or complete. UNH/CCOM-JHC assumes no liability, any damages or loss of any kind that might arise from the use of, misuse of, or the inability to use this web site and/or the materials contained on the web site. UNH/CCOM-JHC assumes no liability for any damages or loss of any kind caused by any errors or omissions in the data contained on this web site. All materials that appear on the UNH/CCOM-JHC web site are distributed and transmitted “as is,” without warranties of any kind, either express or implied, and subject to the terms and conditions stated in this disclaimer.
ASCII XYZ
Winzip (unzipped transfer size in MB)
14.2
http://ccom.unh.edu/unclos/data/**GulfOfMexico_FloridaEscarpment_ASCII_mos.zip
go to http://ccom.unh.edu/unclos/data/**GulfOfMexico_FloridaEscarpment_ASCII_mos.zip
None
2011-05-25
UNH/CCOM-JHC : Center for Coastal and Ocean Mapping/Joint Hydrographic Center, University of New Hampshire
James V. Gardner
Research Professor
Mailing and Physical Address
Chase Ocean Engineering Lab, 24 Colovos Road
Durham
NH
03824
USA
(603) 862-3473
(603) 862-0834
jim.gardner@unh.edu
9:00 AM - 5:00 PM Eastern
Content Standard for Digital Geospatial Metadata
FGDC-STD-012-2002
Universal Time
None
Unclassified
None